1. Field of the Invention
The present invention relates to signal processing, and, in particular, to computer-implemented processes and apparatuses for encoding and decoding image signals for progressive transmission and display.
2. Description of the Related Art
Still images and video images typically require large numbers of bits to represent digitally, even using sophisticated compression techniques. The time required to transmit such images for display at a remote destination, and therefore the time delay between display of successive images, may prove disturbing to the remote viewer. Using a conventional progressive transmission technique, such as those based on the wavelet transform, may prove computationally intensive and therefore time consuming.
It is desirable to provide encoding systems for generating, encoding, and transmitting image signals and decoding system for receiving, decoding, and displaying image signals that reduce the delay to the remote viewer. In particular, it is desirable to provide personal computer (PC) based conferencing systems that provide the capabilities for efficient transmission of images from one conference participant to a remote conference participant over relatively low bandwidth media, such as a PSTN telephone line.
It is, therefore, an object of the present invention to provide computer-implemented processes and apparatuses for efficiently generating, encoding, and transmitting image signals and methods, apparatuses, and systems for efficiently receiving, decoding, and displaying image signals.
It is a particular object that the present invention be applicable to PC-based conferencing systems.
Further objects and advantages of this invention will become apparent from the detailed description of a preferred embodiment which follows.